Study on Control of Single Phase Grid-Connected Inverter Based on Fractional Order PI Controller

Abstract

Abstract:The inverter is a significant part in the single phase grid-connected inverter system. The design of control strategy for photovoltaic power generation system has a decisive role in the system. The fractional order λ PI controller is applied to the gridconnected inverter to improve the single phase photovoltaic grid-connected system performance, which is based on the integrated photovoltaic grid-connected inverter system in this paper. Three parameters of fractional order controller are optimized by Particle Swarm Optimization (PSO), and compared with the integer order PI controller. The results show that fractional order λ PI controller can effectively reduce the harmonic components, and obtain better control effect than the integer order PI controller.

Controller parameters design of a fractional‐order LCL‐type grid‐connected inverter

“…On the other hand, fractional‐order controllers for power converters are gradually being developed. In Jiang et al, 29 the grid current was regulated by using a FOPI controller, which was more effective in reducing current harmonics and had better control performance than the integer‐order proportional integral (IOPI) controller. In Seo and Han 30 and Soriano‐Sánchez et al, 31 a fractional‐order PID controller was used to regulate the direct current (dc)–dc converter, which achieved a smaller overshoot and faster recovery time than an integer‐order PID.…”

Grid-Connected Inverter Based on a Resonance-Free Fractional-Order LCL Filter

“…Based on a conventional integer-order PID controller, Podlubny proposed a fractionalorder PI λ D µ controller in 1999, introducing two adjustable parameters: the integral order λ, and the differential order µ. Compared with the integer-order PID controller, the fractionalorder PI λ D µ controller was more flexible, and it was better to use a fractional-order controller instead of an integer-order controller to control integer-order and fractional-order systems [40][41][42][43]. A fractional-order model of a dc/dc converter in a photovoltaic power generation system was established in [41], and a fractional-order PI regulator was used to control the converter.…”

“…A fractional-order model of a dc/dc converter in a photovoltaic power generation system was established in [41], and a fractional-order PI regulator was used to control the converter. A fractional-order PI λ controller was applied to a grid-connected inverter in [42], and the results showed that the PI λ controller could effectively reduce the current harmonics and obtain a better control effect than a PI controller. Moreover, the fractional-order PI controller was applied to a three-level neutral point clamped (NPC) shunt active power filter in [43].…”